在ZD6系列电动转辙机的启动片通槽一面，车圆台（）台阶，可以避免与减速器内齿轮摩擦。
参考答案：2×Φ75mm
The number of giant pandas is getting _________ because their living areas are becoming farmlands.
A．less and less
B．larger and larger
C．smaller and smaller
D．fewer and fewer
诉讼时效期间届满，当事人丧失：( )
A．实体权利
B．胜诉权
C．起诉权
D．起诉权和实体权利
